Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Category
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Quartz (in a rock matrix)
Quartz (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with traces of titanium, iron, or manganese
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
Coquina
Coquina (a type of limestone)
Jasper (with Manganese or Iron inclusions)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Green Druzy Quartz (Prasiolite)
Silicon Dioxide (SiO2) with inclusions (typically Chlorite or Actinolite)
Limestone
Calcium Carbonate (CaCO3)
Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)
Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)
Optical Calcite (Iceland Spar)
Calcium Carbonate (CaCO3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Limestone (Weathered)
Calcium Carbonate (CaCO3)
Quartzite (River Pebble)
Metamorphosed Quartz-rich Sandstone (SiO2)
Quartzite (Sugar Quartz)
Quartzite (primarily SiO2)
Diamond
Diamond (C)
Quartzite (River Pebble)
Metamorphosed Quartz Sandstone (SiO2)
Rhodonite
Rhodonite (MnSiO3)
Selenite
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Sandstone
Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Impure Chalcedony
Porphyritic Rhyolite (Red Porp)
Porphyritic Rhyolite (Felsic volcanic rock)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Magnetite
Magnetite (Fe3O4)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Ruby in Fuchsite (often sold as Ruby in Zoisite)
Corundum (Al2O3) in Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Fluorite (Purple Fluorite in Matrix)
Fluorite (Calcium Fluoride, CaF2)
Milky Quartz
Silicon Dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide: SiO2 with Iron oxide inclusions)
Rose Quartz
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Rutilated Quartz
Quartz with Rutile Inclusions (SiO2 with TiO2 inclusions)
Smoky Quartz
Silicon Dioxide (SiO2)
Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Blue Kyanite
Kyanite (Al2SiO5)
Diamond
Diamond (Carbon, C)
Red Sandstone
Arenite (primarily Quartz and Feldspar with Iron Oxide cement)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)